The present invention relates to locking mechanisms that are simple and low cost and more particularly to such locking mechanisms that also resist being unlocked by means of tampering without the required key.
Simple, low cost locking mechanisms such as are used to lock washroom dispensers for example, can be unlocked by means of a camming motion induced by the rotation of a key into a cam twister component. Such cam twister components can have a surface that is exposed to the public and can contain a square-shaped recess matching the square-shaped cross-section of the key. While proving to be cost effective and easy to use, this lock design is subject to being unlocked by tampering without the key. The locking mechanism could be activated without the key by using one's finger on the publicly exposed surface of the cam twister or by sticking an object such as a pen, pencil or screwdriver into the square-shaped recess and rotating. The friction between the surface of the cam twister and one's finger (or the object) often proved sufficient to allow the application of enough torque to rotate the cam twister and thus unlock the mechanism without the key.